COMPARATIVE ANALYSIS OF SOIL PHYSICO-CHEMICAL PROPERTIES UNDER MANGO AND CASHEW CROPS IN PART OF SUDAN SAVANNA, NIGERIA

Abstract

To understand the dynamics of mango and cashew cultivation on soil fertility for optimum crop productivity,
this study examined the spatial variability of soil physico-chemical properties in part of Sudan Savanna,
Nigeria. Forty-eight (48) composite soil samples were collected from top and sub-soils at the depths of 0-15
and 15-30cm, respectively. Meanwhile, the samples were collected from 8 selected (20 x 20m) quadrats each in
the fields of mango, cashew, and control site of semi-natural vegetation. The samples were analysed using
standard routine laboratory tests for soil physico-chemical properties essential for determining soil fertility.
One-way analysis of variance was employed to assess the variability of the soil physico-chemical properties
among the farmlands and the control site. The result showed that except for percent sand, all other observed
soil properties in the topsoil and subsoil were statistically heterogeneous under mango, cashew and control
fields. Critical nutrients were therefore significantly higher in the control site than both crop types, though
much better under cashew, indicating a negative impact of cultivation on soil health. Thus, the research
suggests that mango farmers, especially, can enhance their yields by implementing a long-term soil health
monitoring system, collaborating with agricultural research organizations, and implementing best practices
like intercropping with cashew and legumes to improve soil health and nutrient content. More so, both mango
and cashew farmers could complement for the diminishing soil nutrients through the application of organic
fertilizers, and where necessary, the inorganic with special consideration to N, P, K, Ca2+ and Na+